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Finding the Fourth Proportional to 258.80, 387.70 and 210.56

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Solution

The fourth proportional to 258.80, 387.70 and 210.56 is: 315.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.80 : 387.70 = 210.56 : x
  2. Step 2: Convert to fraction form
    258.80/387.70 = 210.56/x
  3. Step 3: Cross multiply
    258.80x = 387.70 × 210.56
  4. Step 4: Simplify right side
    258.80x = 81,634.11
  5. Step 5: Solve for x
    x = 81,634.11/258.80
  6. Step 6: Final answer
    x = 315.43

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.